AGGER, in ancient writers, likewise denotes the middle part of a military road, raised into a ridge, with a gentle slope on either side, to make a drain for the water, and keep the way dry.
The term is also used for the whole road, or military way. Where highways were to be made in low grounds, as between two hills, the Romans used to raise them above the adjacent land, so as to make them of a level with the hills. These banks they called aggeres. Bergier mentions several in Gallia Belgica, which were thus raised, ten, fifteen, or twenty feet above ground.—They are sometimes also called aggeres colecati; and now generally known by the name chausses or causeways.